Targets to boost biofuel production have encouraged multinational companies to buy up land in the developing world, forcing some of the world’s poorest people further into poverty, it is claimed.

The warning comes in a report by a new coalition of charities and faith groups backed by figures such as Bill Gates, the Microsoft founder, and the South African Nobel Peace Prize winner Desmond Tutu.

The “If” campaign, which is being launched today, aims to put pressure on David Cameron to use Britain’s presidency of the G8 to tackle the causes of hunger in the developing world.

The coalition, whose leaders include the film director Richard Curtis, has brought together charities such as Oxfam, Save the Children and the Catholic development agency Cafod with the Church of England, as well as Muslim and Jewish groups.

It points out that there would be enough food to feed everyone in the world – if certain barriers are overcome.

The group is calling for more aid to be targeted towards those most at risk of huger and curbs on “tax dodging” by companies operating in the developing world.

Other targets include the rise of biofuels, which it argues lies behind a series of legal “land grabs” which have swept poor farmers, many of them women, aside.

In its first report, published today, the group claims that crops burned as biofuels in the UK alone would be enough to feed 10 million people a year.

It says that an area the size of London is being bought up in the developing world every six days, depriving poor farmers of land to grow food.

The report calls for EU targets requiring that 10 per cent of transport fuels come from “renewable” sources to be scrapped.

Laura Taylor, head of policy at the Christian charity Tearfund, said: “Setting arbitrary targets saying that a certain percentage of our fuel has to come from them is setting the wrong kind of incentive.

“It means that land which farmers have been using to grow food is now being used for fuel.”

Archbishop Tutu said: "Hunger is not an incurable disease or an unavoidable tragedy, we can make sure no child goes to bed hungry.

"We can stop mothers from starving themselves to feed their families, we can save lives.

"We can do all of this, if we are prepared to do something about it.

"If we challenge our leaders to take action, if they listen to us.

"It's time the world's decision-makers came to the right decision on hunger.

"It's time to end the unnecessary suffering caused by the failure of the current food system. We can make hunger a thing of the past if we act now."